Technical Field
The present invention relates to a radar apparatus that detects a target based on the results of transmission and reception of exploration waves.
Background Art
A radar apparatus is conventionally known that includes a transmission antenna that transmits exploration waves, a reception antenna that includes a plurality of antenna elements, and a signal processing unit. In this radar apparatus, the processing unit detects the distance to and orientation (or azimuth direction) of a target that has reflected the exploration waves, based on the results of reception by the reception antenna of the reflected waves of the exploration waves transmitted from the transmission antenna.
This type of radar apparatus includes that in which the arrangement pattern of the antenna elements configuring the reception antenna is composed of two arrangement patterns, one being at a first interval prescribed in advance and the other being at a second interval that is narrower than the first interval (refer to PTL 1).
In the radar apparatus described in PTL 1, when the orientation of the target detected based on the phase difference between reflected waves received by each antenna element disposed at the first interval matches the orientation of the target detected based on the phase difference between reflected waves received by each antenna element disposed at the second interval, the orientation is recognized as being an appropriate orientation.
In other words, in the radar apparatus described in PTL 1, a plurality of arrangement patterns that differ from each other are used as the arrangement pattern of the antenna elements. When the orientation of the target detected based on reception signals received by the antenna elements disposed in each arrangement pattern matches, the target is considered to be a real image.